In 3GPP (3rd Generation Partnership Project), which is a project aiming to standardize a mobile communication system, it is discussed to utilize a new frequency band in order to cope with a rapid increase of a traffic demand (for example, see Non-Patent Literature 1).
Here, as the new frequency bandwidth, it is considered to utilize a specific frequency bandwidth including a plurality of component carriers having a predetermined bandwidth in such a manner that utilization of a plurality of telecommunications carriers or a plurality of communication systems is permitted.
As the specific frequency band, for example, a band used in Wi-Fi, Bluetooth (registered trademark) or the like, that is, an unlicensed band which does not require license is considered. In the 3PGG, a technique utilizing the unlicensed band in an LTE system (LAA: Licensed Assisted Access) is discussed.